Facebook said on Tuesday that it would begin allowing app developers on its platform to charge users for subscriptions but would require them to stop using Facebook Credits for in-app purchases, according to a blog post.

Facebook does not currently support the subscription model. Instead, developers of apps on its platform make money when users buy virtual goods. They do that either in a currency unique to the app or using Facebook credits.

By the end of the year, real currency will be accepted for subscriptions, and in-app payments will have to rely on in-app currencies. Facebook explained that Credits launched at a time when few apps had their own ersatz currencies. Now, many do, alleviating the need for a "platform-wide virtual currency," the blog post said.

The announcement emphasized the benefits for developers, including the ability to "price the same item differently on a market-by-market basis."

"We anticipate that features built on local currency, like subscriptions and multiple currency price points, will also help developers monetize more effectively," the company said in its materials for developers.

The new model is already being used by some developers, including Kixeye and Zynga, in a private beta test.

"We believe Facebook's new payment product to support pricing in local currency will streamline payment methods on their platform and ultimately offer more flexible pricing options. And, while it's early days, we are looking forward to be bringing players more options to engage in our games through our subscription model and have already begun testing subscriptions in a number of our games on Facebook," a Zynga representative said in an email.